Recently, some vehicles have been equipped with an eco-drive assist apparatus for assisting the driver in eco-drive in view of environmental protection. The eco-drive assist apparatus determines whether the vehicle is traveling efficiently in fuel economy by checking various factors, which may include the degree of depressing the accelerator pedal, the efficiency of the engine and transmission, the traveling speed and the accelerated velocity. When the vehicle is traveling efficiently in fuel economy, the vehicle is in an eco-drive state. When it is determined that the vehicle is in the eco-drive state, an LED (light emitting diode) may be turned ON. The fuel economy may be calculated at an instantaneous time in traveling and may be indicated as an instantaneous fuel efficiency.
Japanese Patent Application Publication No. 2000-205925 proposes displaying a target fuel economy expressed with a mark and an instantaneous fuel economy expressed, with a bar graph on a common index and making it possible for the driver to instantaneously judge whether the instantaneous fuel economy compared with the target fuel economy is good or bad. Japanese Patent Application Publication No. 2007-112257 proposes calculating the time rate of change in the amount of operation of the accelerator pedal every predetermined tune and displaying an eco-drive indicator when the time rate of change is equal to or lower than a threshold value.
In a hybrid vehicle, drive information different from the driver's operation may be displayed when the hybrid vehicle is traveling at a high speed, and may cause the driver to have an uncomfortable feeling. In the hybrid vehicle, the engine is always working when the vehicle is traveling at a high speed. In other words, the engine is working even when the driver releases the accelerator pedal in traveling. Since the engine is working although the driver depresses the accelerator pedal, information indicating that the engine is working is displayed.